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Diffstat (limited to 'lib/libc/gen/unvis.3')
| -rw-r--r-- | lib/libc/gen/unvis.3 | 200 |
1 files changed, 0 insertions, 200 deletions
diff --git a/lib/libc/gen/unvis.3 b/lib/libc/gen/unvis.3 deleted file mode 100644 index 9164f79..0000000 --- a/lib/libc/gen/unvis.3 +++ /dev/null @@ -1,200 +0,0 @@ -.\" Copyright (c) 1989, 1991, 1993 -.\" The Regents of the University of California. All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" 4. Neither the name of the University nor the names of its contributors -.\" may be used to endorse or promote products derived from this software -.\" without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND -.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE -.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE -.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE -.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL -.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS -.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) -.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT -.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY -.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF -.\" SUCH DAMAGE. -.\" -.\" @(#)unvis.3 8.2 (Berkeley) 12/11/93 -.\" $FreeBSD$ -.\" -.Dd December 11, 1993 -.Dt UNVIS 3 -.Os -.Sh NAME -.Nm unvis , -.Nm strunvis -.Nd decode a visual representation of characters -.Sh LIBRARY -.Lb libc -.Sh SYNOPSIS -.In vis.h -.Ft int -.Fn unvis "char *cp" "int c" "int *astate" "int flag" -.Ft int -.Fn strunvis "char *dst" "const char *src" -.Ft int -.Fn strunvisx "char *dst" "const char *src" "int flag" -.Sh DESCRIPTION -The -.Fn unvis , -.Fn strunvis -and -.Fn strunvisx -functions -are used to decode a visual representation of characters, as produced -by the -.Xr vis 3 -function, back into -the original form. -Unvis is called with successive characters in -.Fa c -until a valid -sequence is recognized, at which time the decoded character is -available at the character pointed to by -.Fa cp . -Strunvis decodes the -characters pointed to by -.Fa src -into the buffer pointed to by -.Fa dst . -.Pp -The -.Fn strunvis -function -simply copies -.Fa src -to -.Fa dst , -decoding any escape sequences along the way, -and returns the number of characters placed into -.Fa dst , -or \-1 if an -invalid escape sequence was detected. -The size of -.Fa dst -should be -equal to the size of -.Fa src -(that is, no expansion takes place during -decoding). -.Pp -The -.Fn strunvisx -function does the same as the -.Fn strunvis -function, -but it allows you to add a flag that specifies the style the string -.Fa src -is encoded with. -Currently, the only supported flag is -.Dv VIS_HTTPSTYLE . -.Pp -The -.Fn unvis -function -implements a state machine that can be used to decode an arbitrary -stream of bytes. -All state associated with the bytes being decoded -is stored outside the -.Fn unvis -function (that is, a pointer to the state is passed in), so -calls decoding different streams can be freely intermixed. -To -start decoding a stream of bytes, first initialize an integer -to zero. -Call -.Fn unvis -with each successive byte, along with a pointer -to this integer, and a pointer to a destination character. -The -.Fn unvis -function -has several return codes that must be handled properly. -They are: -.Bl -tag -width UNVIS_VALIDPUSH -.It Li \&0 (zero) -Another character is necessary; nothing has been recognized yet. -.It Dv UNVIS_VALID -A valid character has been recognized and is available at the location -pointed to by cp. -.It Dv UNVIS_VALIDPUSH -A valid character has been recognized and is available at the location -pointed to by cp; however, the character currently passed in should -be passed in again. -.It Dv UNVIS_NOCHAR -A valid sequence was detected, but no character was produced. -This -return code is necessary to indicate a logical break between characters. -.It Dv UNVIS_SYNBAD -An invalid escape sequence was detected, or the decoder is in an -unknown state. -The decoder is placed into the starting state. -.El -.Pp -When all bytes in the stream have been processed, call -.Fn unvis -one more time with -.Fa flag -set to -.Dv UNVIS_END -to extract any remaining character (the character passed in is ignored). -.Pp -The -.Fa flag -argument is also used to specify the encoding style of the source. -If set to -.Dv VIS_HTTPSTYLE , -.Fn unvis -will decode URI strings as specified in RFC 1808. -.Pp -The following code fragment illustrates a proper use of -.Fn unvis . -.Bd -literal -offset indent -int state = 0; -char out; - -while ((ch = getchar()) != EOF) { -again: - switch(unvis(&out, ch, &state, 0)) { - case 0: - case UNVIS_NOCHAR: - break; - case UNVIS_VALID: - (void) putchar(out); - break; - case UNVIS_VALIDPUSH: - (void) putchar(out); - goto again; - case UNVIS_SYNBAD: - (void)fprintf(stderr, "bad sequence!\en"); - exit(1); - } -} -if (unvis(&out, (char)0, &state, UNVIS_END) == UNVIS_VALID) - (void) putchar(out); -.Ed -.Sh SEE ALSO -.Xr vis 1 , -.Xr vis 3 -.Rs -.%A R. Fielding -.%T Relative Uniform Resource Locators -.%O RFC1808 -.Re -.Sh HISTORY -The -.Fn unvis -function -first appeared in -.Bx 4.4 . |
